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Re: 6502 illegal opcodes questions



"Michael J. Mahon" <mjmahon@aol.com> writes:

>>The C64 mainly needed it for its text mode. Unlike the Apple, the 
>>character shapes reside within the Video chip's AND the CPUs normal 
>>memory map, are read over the normal address bus, and can be redefined 
>>by pointing a register to RAM instead of ROM.

[...]
>It was a conscious choice to make the Apple character set fixed.
>(And it's nice to have a character set fully defined at power-up.)

This is a marginal diversion, but I'm not sure what you mean by "fully
defined" since the C64's is, of course, also fully defined in the sense
that it's there. :)

--
      Cameron Kaiser * ckaiser@floodgap.com * posting with a Commodore 128
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